Citations

Abstract Poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi) are a mainstay therapy for homologous recombination (HR)-deficient cancers; however, resistance remains a major clinical challenge. Previously, through a genome wide CRISPR screen, we identified ZNF251 haploinsufficiency as a novel driver of PARPi resistance. In BRCA1 -mutant ( BRCA1 mut ) cells, ZNF251 deficiency led to HR hyperactivation, conferring PARPi resistance that could be reversed by RAD51 inhibition. In this study, we further show that ZNF251 deficiency induces replication stress and a pseudo-senescence state, in which cells exhibit molecular and phenotypic markers of senescence while retaining proliferative capacity. Because senomorphic and senolytic therapies can target senescent cells, we tested whether these approaches could overcome PARPi resistance in ZNF251 -deficient breast cancer cells. Critically, targeting this senescence-like state with either senomorphic agents, such as cytokine inhibitors, or senolytic agents, such as BCL-2 and BCL-XL inhibitors, overcame PARPi resistance ex vivo and in vivo . Importantly, pseudo-senescence was also observed in other PARPi-resistant contexts driven by HR hyperactivation, including 53BP1 - and Shieldin -mutant cells, suggesting that it may represent a broader mechanism underlying PARPi resistance in breast cancer. Furthermore, in two olaparib-resistant, BRCA -mutant triple-negative breast cancer organoid models, treatment with DT2216, a BCL-XL–targeting PROTAC, sensitized both models to olaparib. Together, our work defines a novel pathway linking HR hyperactivation, replication stress, and pseudo-senescence, and positions both senomorphic and senolytic therapies as promising strategies to overcome PARPi resistance in BRCA1 mut breast cancer. Highlights ZNF251 deficiency drives PARP inhibitor resistance through HR hyperactivation, replication stress, and pseudo-senescence in BRCA1 -mutant breast cancer. Senomorphic and senolytic therapies overcome PARP inhibitor resistance in vitro , in vivo , and in patient-derived organoid models. Pseudo-senescence represents a shared vulnerability of HR-hyperactivated PARPi-resistant cancers and can be therapeutically targeted.

Abstract Introduction Despite its prevalence, risk stratification for tachycardia-induced cardiomyopathy remains poorly understood. A deep learning model developed at Mayo Clinic uses standard 12-lead electrocardiograms (ECGs) to predict reduced LVEF (≤35%) in the general population with high accuracy (AUC 0.93) Purpose We investigated the performance of AI-ECG in predicting systolic dysfunction among patients with atrial fibrillation and rapid ventricular response, and compared it with NT-proBNP. Methods We conducted a retrospective study (IRB approval #25-000904) of adult patients (age ≥ 18 years) evaluated across our Clinic enterprise with atrial fibrillation and rapid ventricular response (heart rate >100 bpm), including AF occurring in-hospital and AF at presentation, between January 2017 and May 2025. We excluded patients with a known history of heart failure with reduced EF (<50%). We also collected data on NT-proBNP levels when available within one week of the ECG and echocardiogram. Results A total of 11,801 patients were included, with a mean age of 73.2 +- 12.6 years, 48.6% female and 94.8% White. A combination of AI ECG low EF probability cutoff of 75% had specificity of 96% and 98% NPV in ruling out LVEF < 35%. A combination of AI ECG low EF probability cutoff of 17% and LVEF <35% provided the best balance of sensitivity and specificity, 66% and 78%, respectively with an accuracy of 78%. NT-proBNP data was available on 5,279 patients (48%). Mean NT-proBNP level was 4090 pg/mL. Based on ROC curve analysis, AI ECG was superior to NT-proBNP in predicting LVEF <35% (AUC 0.72 vs 0.59), with accuracy of 77% versus 47% at Youden’s cutpoints of AI-ECG probability of 17% and NT-proBNP level of 1767 pg/mL, respectively Conclusions Our study demonstrates the utility of AI-ECG in predicting reduced LVEF among patients with AF RVR. AI-ECG demonstrated excellent specificity and NPV in ruling out reduced LVEF, serving as a powerful clinical screening tool to assist with the pharmacologic choice of rate control and could change the timing of further echocardiographic evaluation. Our study offers novel insights paving the way for future investigations to help fine-tune and further delineate the role of AI ECG in risk stratifying patients with suspected tachycardia-induced cardiomyopathy, guiding therapeutic and diagnostic clinical decisions

Abstract Background Calcium release channel deficiency syndrome (CRCDS) arises from loss-of-function variants in the RYR2-encoded type 2 ryanodine receptor (RyR2), predisposing patients to sudden cardiac arrest/death (SCA/SCD) despite normal exercise testing. Previously, a novel homozygous RYR2 duplication causing ~ 80% RyR2 reduction was associated with exertion-related SCD. However, how Ca2+ homeostasis is maintained despite RyR2-loss remains unknown, as RYR2-/- animals are non-viable. Purpose To generate a RYR2-knockout (RYR2-KO-/-) induced pluripotent stem cell-derived cardiomyocyte (iPSC-CM) model to dissect compensatory mechanisms sustaining Ca2+ homeostasis and identify arrhythmogenic pathways predisposing to SCD. Methods CRISPR/Cas9 editing was used to introduce a homozygous c.163delT variant into a wild-type iPSC line (control), generating a RYR2-KO-/- model. A patient-derived RYR2-duplication (RYR2-DUP+/+) iPSC line was used for comparison. RyR2 expression was assessed by western blot (WB) and immunofluorescence (IF). Proteome and phospho-proteome were assessed using omics approaches. Intracellular Ca2+ handling was evaluated by Fluo-4 AM imaging (0.5 Hz and long-burst–long-pause [LBLP] protocol). Electrophysiological properties (action potential [AP], and sarcolemmal currents [ICaL, INa and INCX]) were assessed by patch-clamp. Results Despite complete RyR2-loss in RYR2-KO-/- iPSC-CMs as confirmed by WB and IF, contractility and contractile machinery expression was preserved. Ca2+ transient amplitude (ΔF/F0) was reduced markedly in RYR2-KO (0.14±0.01, p<0.01) and RYR2-DUP (0.27±0.2, p<0.01) compared to control (0.52±0.02). Proteomics revealed a significant NCX1 up-regulation and IP3R-interacting protein (ITPRIP) down-regulation in RYR2-KO compared to control, with pathway-analyses showing significant up-regulation of IP3-related pathways. Pharmacological IP3Rs block (2-APB, 10μM) abolished Ca2+ transient generation in RYR2-KO iPSC-CMs (Amplitude: baseline: 0.15±0.01, 2-APB: 0.06±0.01, p<0.01). RyR2-ablation induced electrical remodeling (pA/pF), including ICaL reduction, INCX up-regulation and hyperpolarization of the INa window current in RYR2-KO (ICaL [at 0mV]: -8.5±1.6; INCX [at -110mV]: -4.1±1.1) as compared to control (ICaL:-7.5±3.7, p<0.01; INCX:-1.5±0.5, p=0.02). RYR2-KO CMs demonstrated increased delayed after-depolarizations and beat-to-beat variability as compared to control. Despite Ca2+ sparks abolishment, RYR2-KO CMs displayed higher erratic beating (at 0.5Hz) and arrhythmogenic propensity than control, showing ventricular tachycardia-like events during LBLP stimulation. Conclusions Genetic RYR2-ablation disrupts physiological Ca2+ cycling and triggers electrical remodeling, including INCX up-regulation, overall promoting arrhythmogenesis. Compensatory IP3Rs activation sustains Ca2+ transient generation, revealing a mechanism preserving excitation-contraction coupling that may paradoxically promote arrhythmogenesis in CRCDS.RYR2-KO: Generation and CharacterizationElectrophysiological Assessment

ABSTRACT Background & Aims Metabolic dysfunction‐associated steatotic liver disease (MASLD) is highly prevalent and increasingly recognized as a multisystem cardiometabolic disorder. The global burden, incidence and prognostic implications of coexisting chronic kidney disease (CKD) in MASLD remain uncertain. Methods In this meta‐analysis, we searched MEDLINE and EMBASE from inception through September 25, 2025, for observational studies reporting CKD prevalence and/or incidence among adults (≥ 18 years) with MASLD. The primary outcomes were pooled CKD prevalence, estimated using random‐effects models on the logit scale with the Hartung–Knapp adjustment, and pooled CKD incidence (per 1000 person‐years), estimated using random‐effects models with exact Poisson confidence intervals. Secondary outcomes included all‐cause mortality and cardiovascular, renal and cancer outcomes. Results From 2811 records, 36 observational studies met the inclusion criteria. Twenty‐three studies contributed prevalence estimates (575 615 participants; 56 248 CKD cases) and thirteen studies contributed incidence estimates (27 996 new events). The pooled global CKD prevalence among individuals with MASLD was 15.22% (95% CI 9.69–23.12). The pooled CKD incidence was 22.17 per 1000 person‐years (95% CI 11.44–32.89) in the MASLD population. Hypertension (OR 1.49, 95% CI 1.29–1.72), dyslipidaemia (OR 1.22, 95% CI 1.20–1.24) and diabetes (OR 1.94, 95% CI 1.69–2.22) were associated with higher odds of CKD in the MASLD population. All‐cause mortality rates were 18.28 per 1000 person‐years (95% CI 3.45–33.11) in coexistent MASLD and CKD, more than double those in the MASLD‐only population (7.26 per 1000 person‐years (95% CI 2.97–11.56)). Conclusions Coexistent CKD affects one in seven individuals with MASLD worldwide, conferring a more than two‐fold increased risk of all‐cause mortality compared with individuals with MASLD alone.

Abstract Objective: Antibiotics are frequently prescribed for acute sinusitis despite national guidelines recommending antibiotics only if specific symptom criteria are met. We aimed to define the proportion of acute sinusitis encounters meeting criteria for antibiotic prescribing, characterize prescribing practices, and identify factors associated with guideline-discordant prescribing. Design: This retrospective cohort study included 1,000 randomly selected adult ambulatory encounters with a primary diagnosis of acute sinusitis between January 1, 2024 and March 31, 2024. Encounter notes were reviewed for appropriate antibiotic prescribing criteria as per national guidelines. Encounters were evaluated for drug selection and duration concordance based on local guidelines. A multivariable logistic regression analysis was performed to identify predictors of inappropriate antibiotic prescribing. Setting: Emergency departments, urgent care centers, and primary care clinics. Results: Antibiotic prescribing criteria were met for 67.6% of included encounters. Antibiotics were prescribed in 93.5% of encounters that met prescribing criteria, and 80.2% of encounters that did not. Both drug selection and duration were guideline-concordant in 49.2% of total encounters. On multivariable analysis, predictors of inappropriate antibiotic prescribing included cough (OR 2.15, 95% CI 1.08–4.29; P = 0.03) and symptom duration between 7 and 9 days (compared to <6 days; OR 7.70, 95% CI 3.24–18.31; P < 0.001). Electronic encounters were associated with lower odds of prescribing compared to in-person encounters (OR 0.03, 95% CI 0.01–0.09; P < 0.001). Conclusions: Most encounters for acute sinusitis result in an antibiotic prescription, despite prescribing criteria not being met. These findings may aid antimicrobial stewardship programs in benchmarking and optimizing antibiotic prescribing for acute sinusitis.

Abstract The trabecular meshwork (TM) and ciliary body (CB) regulate aqueous humor dynamics and intraocular pressure (IOP), and TM/Schlemm’s canal (SC) dysfunction underlies glaucoma. Here, we present a spatially resolved multi-omics atlas of human TM and CB, integrating snRNA-seq, scRNA-seq, and snATAC-seq from over one million cells and nuclei across 112 donors with Xenium spatial transcriptomics. We identified 9 major cell classes and 21 cell types, revealing heterogeneity, including undercharacterized fibroblast and epithelial subpopulations. Spatial mapping supported TM fibroblast zonation and CB epithelial organization. Regulatory analyses identified cell type–specific programs, including OTX/PAX networks in CB epithelium and SMAD3/TGF-β signaling in fibroblasts. Integration with glaucoma loci showed enrichment of non-coding variants in regulatory elements associated with POAG and PACG. Age- and ancestry-associated remodeling revealed divergent fibroblast aging with increased PIEZO1 , suggesting impaired outflow and elevated IOP. Together, this high-resolution atlas links cellular, regulatory, and genetic variation to anterior segment function and glaucoma susceptibility.